Rubber band powered toy vehicle

ABSTRACT

A RUBBER BAND MOTOR FOR A TOY TRUCK OR OTHER TOY VEHICLE, WHICH EFFICIENTLY UTILIZES AN ORDINARY RUBBER BAND. THE MOTOR INCLUDES A TAPERED RECEIVING PORTION FIXED TO ONE VEHICLE AXLE, AND THE RUBBER BAND IS POSITIONED TO WIND ONTO THE AXLE AROUND THE TAPERED PORTION SO THAT THE BAND IS WOUND MORE SLOWLY AS IT BECOMES HIGHLY STRETCHED. BAND-ENGAGING POSTS ON THE AXLE AND FRAME ENABLE AN ORDINARY RUBBER BAND TO BE MOUNTED BY MERELY SLIPPING IT OVER TWO POSTS. SEVERAL POSTS ARE PROVIDED ON THE FRAME TO ENABLE RUBBER BANDS OF VARIOUS LENGTHS TO BE EFFICIENTLY UTILIZED.

1971 H. J. FOLSON RUBBER BAND POWERED TOY VEHICLE Filed Dec. 5. 1969 am n/70x AMzy 1/2454 .x/rrmwn United States Patent O 3,611,631 RUBBER BAND POWERED TOY VEHICLE Henry J. Folson, Redondo Beach, Calif., assignor to Mattel, Inc., Hawthorne, Calif. Ihled Dec. 5, 1969, Ser. No. 882,553 Int. Cl. A63h 17/00 US. Cl. 46-206 2 Claims ABSTRACT OF THE DISCLOSURE A rubber band motor for a toy truck or other toy vehicle, which efliciently utilizes an ordinary rubber band. The motor includes a tapered receiving portion fixed to one vehicle axle, and the rubber band is positioned to wind onto the axle around the tapered portion so that the band is wound more slowly as it becomes highly stretched. Band-engaging posts on the axle and frame enable an ordinary rubber band to be mounted by merely slipping it over two posts. Several posts are provided on the frame to enable rubber bands of various lengths to be efiiciently utilized.

- larly, to rubber band type drives therefor.

(2) Description of the prior art One type of motor driven toy vehicle employs a band of rubber or other elastic material having one end fixed to the vehicle frame and the other end coupled to an axle of the vehicle. When the vehicle is rolled backward, the band winds around the axle to propel the vehicle forward when it is released. A clutch is generally employed to couple one end of the band to the axle, so that the axle and wheels thereon can continue to roll forward after the band is completely unwound. The rubber band motors are generally incapable of efficiently utilizing the motive power which can be applied by a rubber band. This is because the band is in such high tension when fully wound that it can spin the wheels before the vehicle starts moving rapidly forward, so that much of the power is lost. If the axle is made very narrow to prevent wheel spinning, it cannot efiiciently utilize the last portion of the band to be unwound, this last portion having only a low tension.

Inasmuch as rubber bands break frequently, it is desirable to enable a child to quickly replace a broken band with another household rubber band. However, while rubber bands of about three inches in length are commonly available, a child often cannot find a band of the exact length necessary for most efficient operation of the toy. If the band is too long, it cannot be easily mounted, while if it is too short, it is partially stretched during mounting and cannot be wound as far.

OBJECTS AND SUMMARY OF THE INVENTION An object of the present invention is to provide a toy vehicle with an elastic band motor which efiiciently utilizes the motive power of the band.

Another object of the invention is to provide a rubber band powered toy vehicle which readily accepts and effi- 3,611,631 Patented Oct. 12, 1971 pered band-receiving portion, and the elastic band is mounted so that it first winds around the largest diameter part and thereafter on constantly decreasing diameter parts of the tapered portion. As a result, when the band is fully wound it is on a narrow diameter axle portion to supply a minimum torque so that the wheels are not accelerated too fast and do not spin on the ground. During the last period of unwind, when the elastic band tension is low, it is turning a large diameter portion of the axle to enable efficient utilization of the band. The tapered construction assures a smooth transition between the beginning and end of band unwind.

The vehicle is constructed to allow a child to install an ordinary household rubber band thereon when the previous rubber band breaks. Both the vehicle frame and 'axle have posts which enable a rubber band to be installed by merely looping its opposite ends over the posts. The vehicle frame is provided with several posts spaced at :different distances from the posts on the axle, so that azi'ubher band which is slightly shorter or slightly longer than average can be efficiently utilized. A child loops oneend of the rubber band over that post on the frame which establishes the band in a very slightly stretched state when the motor is completely unwound.

The novel features of the invention are set forth with particularity in the appended claims. The invention yvill be best understood from the following description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIG. 1 is a perpsective view of a toy truck which utilizes an elastic band motor constructed in accordance with the invention:

FIG. 2 is a bottom view of the toy truck of FIG. 1, with the motor in an unwound state; a

FIG. 3 is a view similar to that of FIG. 2, with the motor in a fully wound state;

FIG. 4 is a sectional view taken on the line 4-4 of FIG. 2;

FIG. 5 is a partial sectional view taken on the line 5-5 of FIG. 2; and

FIG. 6 is a partial sectional view taken on the line 6-6 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a toy vehicle which includes a frame 10, four wheels 12, 14, 16 and 18, and a rubber band motor 20 for propelling the vehicle. As shown in FIG. 2, the rear wheels 16, 18 are fixed to an axle 22 that is rotatably mounted on a pair of brackets 24, 26 that are fixed to the vehicle frame. The axle 22 is part of an axle assembly 27 that is adapted to receive a rubber band 2 8. The rubber band has one end 31 fixed to a post 30 on the frame and an opposite end 29 coupled to the axle assembly 27. A child can wind the motor by moving the truck backward along the ground, to turn the axleassembly in the reverse direction so that the rubber band winds thereon as shown in FIG. 3. When the child releases the truck, the rubber band unwinds from the axle assembly, spinning the axle to propel the truck in a forward direction.

The axle assembly includes a band receiving portion 32 which is fixed to the axle 22 and a. start portion 34 which is rotatably mounted on the axle. The start portion .34, to which one end 29 of the rubber band it attached, has a clutch face with a tooth that canengage a corresponding clutch tooth on the band-receiving portion 3-2 to drive the band-receiving portion in a forward direction. During backward rolling of the truck to wind the rubber band motor, the wheels drive the receiving portion 32 in a reverse direction, and it drives the start portion 'used wh 333E a i everseidirectionto wind the rubber" bandfwhen likely to ran newline-n a "'post is used which istoo ehe-truckziereleased, .the. rubber .banddurns. the-receiving, .-far,-...the band gwill. beinitially. stretched and..it cannot portion 3-2 and start portion 34 in a forward direction to accelerate the truck to a substantial speed.

when ;-the,- truck reaches its maximum speed, .the rub- -b nd; is; completely unwound and the start portion 3J4 icannotatu the forward direction any further. If the start and;.receiving .portions .34, 32 were fixed together, tbeiruclt would-suddenly comev to a halt. However, the clutch teethon-these' portions allows the receiving portion '1 1Q? continue t0 rotate forward, while the clutch teeth 1 n the portions .-32, 34 slip on each other. Accordingly, the .'tr.uclc.can.roll.-a considerable distance. in the forward di- -reetion.-,. e v

As and shown-in start portion34 of the axle assembly has fourposts 36,38,40, 42 arranged :inldh'gzacirclej'having approximately the same circumfer- -'ence; asithe-largestportion of the-axle assembly.-The end 29zof-thearubber band can-be slipped over any one of r foursposts to .attach it to the'start portion. The four ts serye as a guard" to; prevent therubber band from arting to ,wind-around the narrowdiameteraxle 22in- -ste'ad ofswinding'along the bandreceiving-portion 32...,The rband receiving portion 32 has .a tapered regiong44 which. as taz' largest' diameter end46 nearestthe starting portion and anarroiwest diameterportion 48 furthest from the start .PottionISizThus; as the rubber band 28, is wound on the axle assembly, the firstportions are wound around he large part'of. the tapered region while successive pordns are wound around areas of successively decreasing 30 diameter. y I Fhe use of a tapered region on the band receiving portion 32-proniotes efiicient use of the rubber band.. When the truck is released after winding the band, the band initially a't'a high tension and rapidly accelerates 'the truck. The-first portions of the band to be unwound should unwind from a narrow diameter region so that'the band can Q supply only -a relatively small torque to the. axle 22. If the nrst portions to unwind were to contact a large diameter. rgioriof theaxle assembly, they could accelerate ,the wheels so fast that the wheels would slip on the. ground. In such a case, much 'ofithe motor power would be wasted. However, in the motor of this invention, the first .portion '50 of the band to unwind contacts a narrow' diameter part of the axle assembly. Thus, the rubber band initially "applies onlya moderate torque, and the wheels do 'not slip. 5 The,; lastportions of the rubber band to be unwound from the axle assembly, should contact 'al'ar'ge' diameter part of the axle assembly. This is because the rubber {band is .at'a' low tension'at the end of unwinding and can- "not apply a large force. By applying the small force available near the end of unwinding to a large diameterportion-of theaxle assembly, the small forcecan'still supply "a siibstantial torque to further accelerate the truck so it attains an 'even' higher speed. i

The post 30 around which the end 31 'of'the rubber band extends is positioned at one side of 'the' v'ehicle *rmme; causes the rubber band 28 to extend in' 'a 'dir'ection to urge the start portion 34 of the axle assembly towa'r'd engagement with the receiving portion 32 of-the assembly, to assure their engagement during winding-of tliebai1d-.'In addition'topost 30, two other posts 52, 54 are provided which are at different distances' from' the "startportion'34. The provision of three posts atfdilfere'nt distances from the start portion 34 enables the efiicierit use: of "rubber bands of a range of sizes. This is important becaus'e' the rubber bandinitially supplied with the vehicle .fn'iaybre'ak and have to be replaced. The toyis'desi'gned fiso that-a "child may utilize an ordinary household'r'u'bber -band, which may range in length between limits such as 2-/i"inches-and' 3% inches. The child'attaches-the'band "to" one of theposts 30, 52 or 54 which provides just "enough tension to keep the band in place." If a' post is 'ch is too close to the axle assembly, the band supply a maximum amount of power. The provision of several posts allows for mounting at a nearly optimum distance. W

The .motorcan bev wound by grasping one, of the .Wheels 16 ch18 and turningfiebackwards, However, a 'person is 'the'nlikelyrto overwind themotor and .b'reak the' band. It is generally preferabletowind the" motor by rolling the vehicle backward on the ground. The wheels 16, 18 :may be;'constructed of a hard plastic'which has a relatively low coefficient of friction so it can readily spin on the ground. Whenachild presses-down on the vehicle with only moderateforce while rolling ,itbaclgwards, the wheels willslide' an the ground aften'thnrotor is wound siifii eien l so "that further backward" move ent *of-- the vehicle will not overwin'd the band and break it. course, it is possibleto'p'res's down 'hard'enough on the vehicle'to still break the fbanddu'ring backward *rolling, butgthis isless likely to occur'than with hand turning. "Thus, the invention-providesa' toyve hicle which efficiently utilizes the motive' power 'which can be supplied by ari 'elas'tic band; Th'e'vehicle"ha's"'an axle-assembly with a-Ttaperedfportion for receiving the elastic band -'to minimize the torque supplied" when the band; is fully wound, so as to prevent wheel slippage. Thisis especially important for vehicles with wheels which are made to slip easily to prevent overwinding. 'I h etapered portion of the axle assembly-also enables eventhe last portions to be unwound, of the. rubber band,;to contribute to vehicle acceleration. The members which hold theband are constructed to' allow an ordinary loop-shaped household rubber band to Be easily mounted thereon, andto allow efiicient utilization of rubber bands within a range -of sizes, Many variations in the construction of,,.the @vehicle' can be employed'to increase performance. For example;it"is'possible to utilize a front axle which is similar to thereartaxle, and to allow the rubber band to extend between starting portions on the two axles so that all fourwheels accelerate .the truck. Although particular embodiments of the invention have I beenidescribediand illustrated herein, it is recognizedthat modifications and variations may readily occur to those .jslgille d in. thjefart, andconsequently, it is intended that the claims be; interpreted to cover such modifications andfiq ivale'nts, What is'claimed' is: y v p 1.. A toy vehicle coinprisingf anaxle assemblyrotatably'mounted onsaid frame, 'fincludingan axle havinga first-end, a second "end and,an'iintermediatefportion, a tapered,fband-rece'ivingfpor'tion fixed onfsaid axle, saidband-receiving portion having a small-diameter end adjacent said end said axle anda lar'ge-diameterlendadjacent said. intermediate portion of said axle, and .a I startportionrotatably. mounted onsaid aneadiacent said large-diameter endof said'fta'pered portion; wheel means attached to said axle to rotate with it; first means forcoupling 'one end of 'anelongated'jelastic member to said start portion, said first nieansfor esuming comprisinga plurality of axially-extending I postsmountedon, said startportion and arranged .in a circleof a diameter at least about as large as the larger diameter end ,of said tapered portion, said posts extending axially overf'said second lendof said axle,'fjwhereby. 'said posts serveffas, a guard preventg said 'jelastic member from .winding ab'outj said secondmeans for coupling,,a.,second end of said elastic member,.to said vehicle ,solthat; the elastic member extends vvith ;:av directional component angled toward I thetismall-diameter end of said .tapered portion .-;--whereby rotation of said axle assernblycauses said elasticmember to pullsaid start portion into engagement with said large-diameter end of said tapered References Cited portion and to wind on portions of said tapered UNITED STATES 1P ATENTS portion of progressively smaller diameter; and one-way clutch means on said start portion and said 1,203,438 10/ 1916 Webster 46-206 large-diameter end of said tapered portion in facing 5 1,930,450 12/1931 Langos r 46-4206 relationship for forming a driving connection when 2,590,515 3/1952 Derham 46206 said elastic member is wound on said tapered portion. 2,749,660 6/ 195 6' Zimentstaek 46-206 2. The toy vehicle described in claim 1 wherein: said second means for coupling comprises a plurality FOREIGN PATENTS of posts mounted on said frame at diiferent distances 10 from said large diameter end of said tapered receiv- 1,084,919 1/1955 France 46-206 ing portion of said axle assembly, whereby to hold firmly, but without substantial initial stretching, LOUIS MANOENE Pnmary Exammer elastic members of different unstretched lengths. D. L, WEITNHOLD, Assistant Examiner 

